A semiconductor device according to the present invention includes a first conductive-type semiconductor layer, a second conductive-type base region that is arranged in the front surface portion of the semiconductor layer, a plurality of trenches that extend from a front surface of the semiconductor layer beyond a bottom portion of the base region with an active region being defined therebetween, a plurality of first conductive-type emitter regions that are arranged in the active region, each connecting the trenches adjacent to each other, a gate electrode that is embedded in the trench, an embedding insulating film that is embedded in the trench on the gate electrode and that has an upper surface in the same height position as the front surface of the semiconductor layer or in a height position lower than the front surface and an emitter electrode that covers the active region and the embedding insulating film and that is electrically connected to the base region and the emitter region.

A bipolar transistor and a method for fabricating a bipolar transistor are disclosed. In one embodiment the bipolar transistor includes a semiconductor body including a collector region and a base region arranged on top of the collector region, the collector region being doped with dopants of a second doping type and the base region being at least partly doped with dopants of a first doping type and an insulating spacers arranged on top of the base region. The semiconductor body further includes a semiconductor layer including an emitter region arranged on the base region and laterally enclosed by the spacers, the emitter region being doped with dopants of the second doping type forming a pn-junction with the base region, wherein the emitter region is fully located above a horizontal plane through a bottom side of the spacers

Provided are a power device having an improved field stop layer and a method of manufacturing the same. The power device includes: a first field stop layer formed of a semiconductor substrate and of a first conductive type; a second field stop layer formed on the first field stop layer and of the first conductive type, the second field stop layer having a region with an impurity concentration higher than the first field stop layer; a drift region formed on the second field stop layer and of the first conductive type, the drift region having an impurity concentration lower than the first field stop layer; a plurality of power device cells formed on the drift region; and a collector region formed below the first field stop layer, wherein the second field stop layer includes a first region having a first impurity concentration and a second region having a second impurity concentration higher than the first impurity concentration.

A semiconductor device according to the present invention includes a first conductive-type semiconductor layer, a second conductive-type base region that is arranged in the front surface portion of the semiconductor layer, a plurality of trenches that extend from a front surface of the semiconductor layer beyond a bottom portion of the base region with an active region being defined therebetween, a plurality of first conductive-type emitter regions that are arranged in the active region, each connecting the trenches adjacent to each other, a gate electrode that is embedded in the trench, an embedding insulating film that is embedded in the trench on the gate electrode and that has an upper surface in the same height position as the front surface of the semiconductor layer or in a height position lower than the front surface and an emitter electrode that covers the active region and the embedding insulating film and that is electrically connected to the base region and the emitter region.

We disclose a bi-directional bipolar junction transistor (BJT) structure, comprising: a base region of a first conductivity type, wherein said base region constitutes a drift region of said structure; first and second collector/emitter (CE) regions, each of a second conductivity type adjacent opposite ends of said base region; wherein said base region is lightly doped relative to said collector/emitter regions; the structure further comprising: a base connection to said base region, wherein said base connection is within or adjacent to said first collector/emitter region.

A two-surface bidirectional power bipolar transistor is constructed with a two-surface cellular layout. Each emitter/collector region (e.g. doped n-type) is a local center of the repeated pattern, and is surrounded by a trench with an insulated field plate, which is tied to the potential of the emitter/collector region. The outer (other) side of this field plate trench is preferably surrounded by a base connection region (e.g. p-type), which provides an ohmic connection to the substrate. The substrate itself serves as the transistor's base.

A method for manufacturing a semiconductor device having an SiC-IGBT and an SiC-MOSFET in a single semiconductor chip, including forming a second conductive-type SiC base layer on a substrate, and selectively implanting first and second conductive-type impurities into surfaces of the substrate and base layer to form a collector region, a channel region in a surficial portion of the SiC base layer, and an emitter region in a surficial portion of the channel region, the emitter region serving also as a source region of the SiC-MOSFET.

An IGBT includes an n-type drift layer, a p-type base layer and an n-type emitter layer formed on an upper surface of the n-type drift layer, and a p-type collector layer on a lower surface of the n-type drift layer. A FWD includes the n-type drift layer, a p-type anode layer formed on the upper surface of the n-type drift layer and an n-type cathode layer formed on the lower surface of the n-type drift layer. A p-type well is formed on the upper surface of the n-type drift layer in a wiring region and a termination region. A wiring is formed on the p-type well in the wiring region. The p-type well has a higher impurity concentration and is deeper than the p-type anode layer. The p-type well is not formed directly above the n-type cathode layer and is separate from a region directly above the n-type cathode layer.

A semiconductor device includes a switching device region including an active region having a first conductivity-type emitter region formed on an upper surface side of a first conductivity-type substrate, a second conductivity-type base region formed on an upper surface side of the substrate, a second conductivity-type collector layer formed on a lower surface side of the substrate, and a diode region having a second conductivity-type anode layer formed on the upper surface side of the substrate and a first conductivity-type cathode layer formed on the lower surface side of the substrate, wherein the cathode layer is separated from the active region when planarly viewed, and on an upper surface side of the active region, a second conductivity type high-concentration region having an impurity concentration higher than that of the anode layer is formed.

A Reverse Bipolar Junction Transistor (RBJT) integrated circuit comprises a bipolar transistor and a parallel-connected distributed diode, where the base region is connected neither to the collector electrode nor to the emitter electrode. The bipolar transistor has unusually high emitter-to-base and emitter-to-collector reverse breakdown voltages. In the case of a PNP-type RBJT, an N base region extends into a P epitaxial layer, and a plurality of P++ collector regions extend into the base region. Each collector region is annular, and rings a corresponding diode cathode region. Parts of the epitaxial layer serve as the emitter, and other parts serve as the diode anode. Insulation features separate metal of the collector electrode from the base region, and from P type silicon of the epitaxial layer, so that the diode cathode is separated from the base region. This separation prevents base current leakage and reduces power dissipation during steady state on operation.